GHR基因exon 9和exon 10多态性与西农萨能奶山羊产奶性能的相关分析

Polymorphism of exon 9 and exon 10 of GHR gene and its relationship with milk performance of Xinong Saanen dairy goat

针对GHR基因exon 9和exon 10设计了2对引物,采用PCR-SSCP技术检测该基因这2个位点在西农萨能羊群上的单核苷酸多态性,同时研究其对产奶性能的影响。结果表明:exon 9具有多态,exon 10不存在多态性。Exon 9位点在西农萨能山羊中检测到NN型和NT型,纯化测序发现有1个SNP位点,NN型与NT型相比在该片段第241 bp处有1个G→T的突变;NN和NT基因型之间产奶量的最小二乘均值差异显著(P<0.05):NN基因型在各胎次产奶量和平均产奶量等指标上均好于NT基因型,其中在第3胎的产奶量和第4胎产奶量2项指标上都达到显著水平(P<0.05)。研究结果提示:GHR基因exon 9对奶山羊产奶量有显著影响,因此认为GHR基因exon 9位点可作为奶山羊高产奶量的标记辅助选择的有效分子标记。

The GHR gene was studied as a candidate gene for milk performance in Xinong Saanen dairy goats. Two pairs of primers were designed to detect single nucleotide polymorphisms of exon 9 and 10 of GHR gene by PCR-SSCP. The results showed that products amplified by exon 10 did not exhibit polymorphisms. For exon 9, two genotypes （NN and NT） were detected in Saanen dairy goats. Sequencing revealed one mutations of the GHR gene in the genotype NN in comparison to the genotype NT; the difference in the least squares means （LSM） for milk yield between NN and NT was significant（P〈0.05）. The milk yield of individuals with genotype NN was higher than those with genotype NT in the third and fourth lactation periods （P〈0.05）. Based on these results, the GHR gene had significant positive effects on milk performance of dairy goats and the exon 9 of the GHR gene may be regarded as an effective molecular marker on the MAS program for the milk performance of dairy goats.